Gloves are submitted to a lot of stress: shocks, abrasion, stretching. They often tear, or hole up. Gloves are typically made of silicone rubber.

Household cyanoacrylate (a.k.a "Super Glue" or "Krazy Glue") does not adhere well, or at all, to silicone. A primer, LOC770, can be used to increase adherence.
For holes, silicone sealant works well, as it acts as a filler. "Aquarium" silicone appears to contain loads of VOCs (it stinks) which may lead to increased adherence.

Large tears can be mended (sewn) with dental floss first, then covered with silicone.

Sources:

• DAP Aquarium Silicone at Amazon
  
• Loctite 770 at Amazon
  

Fins

Most fins are made of vulcanized rubber. Rails can come undone, and be glued back on.
Footpocket tears are unfortunately rarely fixable, as that area comes under high forces.
Same for cracks in the blade; stress-related fractures in the blade are not uncommon, and doom the entire fin.

Breier fins are glued with a rubber-friendly cyanoacrylate.

Sources:

• BSI IC-2000 at Amazon
  

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